hards vs oakum

hards

noun
  • The short coarser fibers of flax or hemp; tow. 

oakum

noun
  • The coarse portion separated from flax or hemp in hackling. 

  • A material, consisting of tarred fibres, used to caulk or pack joints in plumbing, masonry, and wooden shipbuilding. 

How often have the words hards and oakum occurred in a corpus of books? (source: Google Ngram Viewer )